1. Field of the Invention
The present invention relates to a novel automatic water feed method in lavatory and a novel automatic water feed mechanism in lavatory, using an artificial retina sensor which visually recognize an user of a lavatory and a sensor unit which has light emitting means for emitting light to the user when the ambient lightness becomes lower than a specified level, and light receiving means for receiving the light reflected from the user.
2. Description of the Prior Art
FIG. 17 shows a conventional hand washer 602 for feeding water automatically by using a light reflection system. In FIG. 17, a sensor unit 603 comprises light emitting means (not shown) for emitting light L1 such as infrared ray or near infrared ray toward the user U, and light receiving means (not shown) for receiving reflected light L2 coming from the user U. When the reflected light L2 is received, water is supplied from a discharge pipe 602a installed on a mounting plane 601 of a basin 600 of the hand washer 602.
However, since the light emitting means is set so that the light L1 may be directed toward a bowl 604, if the bowl 604 is made of stainless steel or other metal of high reflectivity and the bottom is shallow, similar light other than the reflected light L2 may enter the light receiving means, which may cause a wrong detection.
On the other hand, an automatic water feed mechanism comprising an image pickup unit for taking the image of hand of the user projected to the lower part of an automatic lavatory main body is proposed (see Japanese Unexamined Patent Publication No. 11-36396 gazette), but since the image pickup unit has a camera function, if a hand of the user is present in the water feed sensing range, it cannot be detected in a dark place or environment.
The invention is devised in the light of the above background, and it is hence an object thereof to be capable of sensing the user of the lavatory securely, and also sensing the user of the lavatory even in a dark place or environment.
To achieve the object, the invention presents an automatic water feed method in a lavatory characterized by controlling the water feed action of the lavatory such as flush urinal and hand washer by visually recognizing the user of the lavatory by means of an artificial retina sensor, and also controlling the water feed action of the lavatory by a sensor unit which has light emitting means for emitting light to the user when the ambient lightness becomes lower than a specified level, and light receiving means for receiving the light reflected from the user.
According to other aspect, the invention also presents an automatic water feed mechanism in a lavatory comprising a lavatory such as flush urinal or hand washer, an artificial retina sensor for visually recognizing the user of the lavatory, a sensor unit having light emitting means for emitting light to the user and light receiving means for receiving the light reflected from the user, and a controller for controlling the water feed action of the lavatory on the basis of the output from the artificial retina sensor or the output of the sensor unit.
That is, from the viewpoint that the artificial retina sensor or camera unit can visually recognize the user only in an illuminated light place, the invention is intended to activate the sensor unit such as infrared ray sensor of light reflection system not influenced by the lightness, instead of artificial retina sensor, in a dark place. That is, the invention, if the artificial retina sensor fails to function due to power failure or the like during use of lavatory, the infrared ray sensor functions instead.
Accordingly, the controller for controlling the water feed action of the lavatory of the invention has a darkness judging function to judge if the ambient lightness is light enough to recognize the user visually by the artificial retina sensor or not.